Influence of Dissolved Organic Carbon (DOC) on Growth of Three Fish Species in North-Temperate Lakes

Dissolved organic carbon (DOC) has strong effects on the productivity of lake ecosystems and the physical habitat available for fish, potentially influencing the productivity of fish and fisheries. In this study, we tested the hypothesis that DOC concentration is negatively correlated with growth rates of three common North American fish species: yellow perch (Perca flavescens), walleye (Sander vitreus), and lake trout (Salvelinus namaycush). We estimated growth rates using length-at-age data from 45 lakes with widely varying DOC concentrations, and used multiple regressions to test for DOC effects on growth while controlling for factors such as fish abundance and lake nutrient concentrations. Our results reveal species-specific effects of DOC on fish growth and productivity, and help to explain recent observations that DOC influences fish yield from inland fisheries.